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E63 / E64 6 Series (2004 - 2010) The E63/E64 BMW 6 Series builds on BMW's sporty heritage with aggressive lines and an incredible motor to back the design up. Available in coupe and convertible trims with a standard 4.8 liter engine producing 360 horsepower and 360 lb-ft of torque, the 6-series is a popular choice that exceeds expectations.

High engine load, can cause damage to catalytic converters - Warning on iDrive

Hello all,

Hope somebody can shed some light on this issue.

I haven't been using my car much for the past week as I've not been working. My car has mostly been sat around. I gave the car a 2 day detail, just getting it up to my standards as I've just recently purchased her.

I switched the car on today to move it after cleaning the interior, the engine was cold as I had not moved it since yesterday morning. When the car was warming up, it started juddering and a warning them came on the iDrive screen soon after with the following message:

High engine load, can cause damage to catalytic converters
(might be shown differently on screen)

It came on screen briefly then went off.

I am going to get the codes read at my local BMW specialist but I am really worried and wanted some advice prior to getting the codes read.

The misfiring engine probably resulted in the car running rich. A large amount of unburnt fuel would be picked up by the O2 sensor and warn you that the cats will basically burn up if you keep driving very rich.

You can drive it to a dealer if the misfire clears itself after the car warms up but if the car is running very rough even after warming up for a few minutes it might be a good idea to tow it. Cats are not cheap.

The misfiring engine probably resulted in the car running rich. A large amount of unburnt fuel would be picked up by the O2 sensor and warn you that the cats will basically burn up if you keep driving very rich.

You can drive it to a dealer if the misfire clears itself after the car warms up but if the car is running very rough even after warming up for a few minutes it might be a good idea to tow it. Cats are not cheap.

Thank you for your reply mate.

Why do you think the car is misfiring?

I've had a cold start rough idle for a while now but it's not really worried me as I thought it was normal. The weird thing is, the rev needle doesn't fluctuate, the car just vibrates. until now nothing has come up on the iDrive.

Today i started her up and there was no EML light present and on the iDrive the fault menu says 'OK - No Faults'.

I took the car to the local BMW specialists who advised me that it should be okay as the fault has gone away and the EML light hasn't activated and said to come back if it did. Should I listen to him and carry on until the warning comes up again? Is this a risk?

Is it normal for the idle to be lumpy on a cold start or is this pointing towards a problem?

Hi ! Whilst I have never had that warning light, there have been occasions when the car was lumpy on tickover but it soon passed when I revved the engine or it got warmer. It was not a regular thing but noticeable when it happened.
I do not know how many miles on the clock but you may find there are some things which may mitigate it happening in the future, especially if your local dealer said there were no codes registered.

I have a 04' 645ci and never had a problem with it at all but yesterday started it up and had the same problem. Very rough idle with the same message displayed on the iDrive. I did not attempt to revv the engine, but just turned the car off and restarted it and nothing came up.

Since then I have started and run the car numerous times with no problems. Hoping its nothing serious...

Hi ! I see you have 645's so they may have some mileage on them, so as a preventative measure that really does have an impact, is to clean the injection system with BG44K, comes in a can follow the simple instructions make sure you have a full tank, this stuff really works!!! Also consider if you should clean the MAF sensor, it requires a special cleaner which is available but you really must follow the instructions, it is a very easy thing to do BUT do it wrong you can damage the sensor and that is not cheap. Both these things are worth doing anyway not expensive and can make a real difference if you have any kind of rough or lumpy running. Finally if it persists and you do have high mileage consider changing the fuel filter, it should be changed at some point in time anyway, again easy to do just a bit smelly with the petrol that naturally comes out when you strip it out!!! Hope these things help or at least worth considering even for prevention.....

Ah thanks for the advice, will buy a can of cleaner when I get a chance and report back. My E63 has done just over 65k miles now, had 58k when I brought it 9 months ago, and has since had a oil service and new spark plugs and is only run on Shell V-power. Currently running perfect but will run the cleaner through the system anyway and see how it goes.

Ah thanks for the advice, will buy a can of cleaner when I get a chance and report back. My E63 has done just over 65k miles now, had 58k when I brought it 9 months ago, and has since had a oil service and new spark plugs and is only run on Shell V-power. Currently running perfect but will run the cleaner through the system anyway and see how it goes.

Could do without any surprise expenses just before Christmas!

BG44k should be used every 20k or so, on mine it did improve running even consumption, but knowing the injectors and tops of the pistons got a decent clean makes it worthwhile, just for the record Lexus, Bentley etc. put this stuff in at every service......

Hi ! Whilst I have never had that warning light, there have been occasions when the car was lumpy on tickover but it soon passed when I revved the engine or it got warmer. It was not a regular thing but noticeable when it happened.
I do not know how many miles on the clock but you may find there are some things which may mitigate it happening in the future, especially if your local dealer said there were no codes registered.

The local independent specialist didn't even plug the reader into the car as there were no fault codes showing on the iDrive or dashboard...should he have still checked?

My car is currently at 84k miles.

So it's not only me who has a lumpy cold start idle every now and again...

Quote:

Originally Posted by mayhs

Must be something to do with the weather.

I have a 04' 645ci and never had a problem with it at all but yesterday started it up and had the same problem. Very rough idle with the same message displayed on the iDrive. I did not attempt to revv the engine, but just turned the car off and restarted it and nothing came up.

Since then I have started and run the car numerous times with no problems. Hoping its nothing serious...

Glad to know I ain't alone on this!! I was really scared!

Do you think it's to do with the UK's cold weather?

Mine hasn't come back also...but then I've only driven it twice since then (on holidays at the moment so I don't need to use the car).

Maybe it's a common 645 issue when the temperature gets colder?

Please update me if you have any future issues or the fault is diagnosed - I will really appreciate it. I will do the same also

Quote:

Originally Posted by 645/333

Hi ! I see you have 645's so they may have some mileage on them, so as a preventative measure that really does have an impact, is to clean the injection system with BG44K, comes in a can follow the simple instructions make sure you have a full tank, this stuff really works!!! Also consider if you should clean the MAF sensor, it requires a special cleaner which is available but you really must follow the instructions, it is a very easy thing to do BUT do it wrong you can damage the sensor and that is not cheap. Both these things are worth doing anyway not expensive and can make a real difference if you have any kind of rough or lumpy running. Finally if it persists and you do have high mileage consider changing the fuel filter, it should be changed at some point in time anyway, again easy to do just a bit smelly with the petrol that naturally comes out when you strip it out!!! Hope these things help or at least worth considering even for prevention.....

Thank you for the advice matey

Where can I get this BG44K cleaner from?

How often is the fuel filter meant to be changed and how do you carry out this change? Don't think mine has ever been done!

I'm guessing this BG44K is just like the Redex where you pour it into the the fuel tank full of fuel?

Quote:

Originally Posted by mayhs

Ah thanks for the advice, will buy a can of cleaner when I get a chance and report back. My E63 has done just over 65k miles now, had 58k when I brought it 9 months ago, and has since had a oil service and new spark plugs and is only run on Shell V-power. Currently running perfect but will run the cleaner through the system anyway and see how it goes.

Could do without any surprise expenses just before Christmas!

I will probably do the same myself

Lets hope none of us face a large expense!

Quote:

Originally Posted by 645/333

BG44k should be used every 20k or so, on mine it did improve running even consumption, but knowing the injectors and tops of the pistons got a decent clean makes it worthwhile, just for the record Lexus, Bentley etc. put this stuff in at every service......

The local independent specialist didn't even plug the reader into the car as there were no fault codes showing on the iDrive or dashboard...should he have still checked?

My car is currently at 84k miles.

So it's not only me who has a lumpy cold start idle every now and again...

Glad to know I ain't alone on this!! I was really scared!

Do you think it's to do with the UK's cold weather?

Mine hasn't come back also...but then I've only driven it twice since then (on holidays at the moment so I don't need to use the car).

Maybe it's a common 645 issue when the temperature gets colder?

Please update me if you have any future issues or the fault is diagnosed - I will really appreciate it. I will do the same also

Thank you for the advice matey

Where can I get this BG44K cleaner from?

How often is the fuel filter meant to be changed and how do you carry out this change? Don't think mine has ever been done!

I'm guessing this BG44K is just like the Redex where you pour it into the the fuel tank full of fuel?

I will probably do the same myself

Lets hope none of us face a large expense!

Hmm that's reassuring!!!

Redex and the other cheap stuff are useless in the main. BG44K is expensive at £20+ per tin and can be bought easily off Ebay. You can search for the cheapest around. As for the fuel filter they reckon at around 60k miles, nothing definitive whilst never guaranteed, many parts changed are for preventive reasons especially if keeping your or coming into a 6 series at the 60K miles region. These cars will serve you well if you look after them. Another point in this weather do not put any other antifreeze in your engine other than BMW 's OEM. Major major reasons for doing this a bit like only BMW transmission oil, severe damage if you use others, even if they are cheaper. Funnily though some BMW stuff is not as expensive as you may think.

Other things to consider is keeping the battery on trickle charge when not in us, or if you are using the car only once a week ish, again if you don't follow this advice you will definitely experience problems at some point, many of them apparently having no bearing on the battery but this is the cause!!!!! These cars are extremely dependant on a good and consistent power supply, again read the threads bucket loads !!!!

Finally fault codes do not come up on the Idrive, all they tell you is the basic vehicle systems, you need a code reader and a good independent should have the right equipment, which plugs into the cars diagnostic port!!!!

Use ONLY BMW coolant (the blue stuff) it's pH balanced and has excellent anti-corrosion inhibitors

BG44K is much better than most additives. You get what you pay for.

I hope the shop did not give you the "iDrive showed no errors" as an excuse for not reading codes. 99% of codes do not cause a message to show.

Fuel filler should be changed every 30K to 60K miles depending on the quality of gas in your area. If you are in a rural area where high octane gas is sold in low volume, it can get contaminated which will clog up your filter faster than normal.

Just a quick update. I finally got around to buying a can of BG44K and the car does seem to run smoother although it could just be me. I used the can over 2 fill ups (normally fill 40 litres at a time) and have since had one more fill up on shell V-Power (only ever used V-power since owning the car). However this morning, after a really cold night in the UK, I came to start the car this morning and had the light come up on the dash and message pop up on the Idrive. this time the car did not seem to be misfiring like it did last time, but wasn't running smooth. I turned the car off and waiting a few seconds, then restarted with no problems whatsoever.

It does seem to be something to do with the weather, just wondering if anyone else has had the problem with the recent cold snap in the UK?

Hi ! When I used BG44K, I did one full can it into a full tank of fuel and ran it down to empty before refilling. the reason was a) not to dilute the solution b) this stuff needs time to break down contaminates in the engine and fuel system and running a full tank down gives greater opportunity.
Also I know this stuff works and found it worthwhile to do it after the next 10k.
In the UK we do not have the range available that you have in Canada and the States so this is probably the best we have!!!
There are companies in the UK now offering the full fuel delivery clean where they link your car to a separate fuel supply with all of the cleaners for about £85.......
What is an issue for all cars but especially the 6 series as you are now aware is the battery, and really cold conditions (but nothing compared to other countries) can have an affect!!!!

Hi ! When I used BG44K, I did one full can it into a full tank of fuel and ran it down to empty before refilling. the reason was a) not to dilute the solution b) this stuff needs time to break down contaminates in the engine and fuel system and running a full tank down gives greater opportunity.
Also I know this stuff works and found it worthwhile to do it after the next 10k.
In the UK we do not have the range available that you have in Canada and the States so this is probably the best we have!!!
There are companies in the UK now offering the full fuel delivery clean where they link your car to a separate fuel supply with all of the cleaners for about £85.......
What is an issue for all cars but especially the 6 series as you are now aware is the battery, and really cold conditions (but nothing compared to other countries) can have an affect!!!!

Sorry I meant that I did put the BG44K, but over 2 tanks of 40litres each and ran it empty. Then refilled as normal using Shell V-power only.

And I had the spark plugs changed recently, about 2 months ago.

Problem seems quite sporadic, thankfully restarting the car seems to fix the issue, however it does make me worry that 'somethings not quite right'

If your plugs are "fouled" and not giving you a good spark it can result in the car running "rich" (unburnt gass in the combustion chamber) and damage to the cats will occur sooner or later and the car may hesitate etc...

replacing the plugs will give you back a strong spark and the car will run smoother.

PS...

I just had the same "warning message" ....had the plugs changed and added a can of BG44 and its running smooth again...

The un-burnt fuel that can result in you getting the "warning message"

That warning message only came up once and that was for about 5 seconds? Because the problem didn't persist, I will look at it as a glitch until it reappears.

I went back to the BMW specialist who I use regularly. He read the codes stored and informed me there were no fault codes stored and that everything was fine (ie spark plugs/coils etc).

He then he went on to explain a lot of BMW 545's and 645's have come in with the exact same as I've been experiencing, where the car judders/vibrates fiercely when warming up (cold start). He suggested replacing the breather? I don't know what the exact name is referring to this component. I have attached photos of them below so you can identify what it is exactly.

He suggested replacing these breathers as most likely there may be a pin hole in the rubber as it's starting to get old causing the car to vibrate on cold start ups. The cars which had this issue improved after this part was changed. For £70 including parts and labour I agreed to have them changed. Since then thankfully the issue has not come back so I'm guessing his diagnosis was correct!

Also, he explained that I may have got this error on the iDrive due to the vibration as its trying to adjust fuel/air mixture as a result of the vibration? Something along those lines. Some of you may know what he is referring to.